Assembly mechanism for metal sleeve base



Nov. 19, 195-7 .1. F. SCHMERHEIM 2,313,330

ASSEMBLY MECHANISM FOR METAL SLEEVE BASE Filed June 23. 1953 2Sheets-Sheet 1 Inventor": John F Schmerheim, by Mn His Attorney Nov. 19,1957 J. F. SCHMERHEIM 2,813,330

ASSEMBLY MECHANISM FOR METAL SLEEVE BASE File d June 23, 1953 2Sheets-Sheet 2 Inventor:- '\John F." Schmerheim by His Attorney UnitedStates Patent 6 ASSEMBLY MECHAlgghS IEFR METAL SLEEVE John F.Schmerheim, South Euclid, Ohio, assignor to General Electric Company, acorporation of New York Application June 23, 1953, Serial No. 363,638

2 Claims. (Cl. 29-282) The present invention relates to an assemblymechanism for a metal sleeve base of the type disclosed and claimed inthe copending application of Donald D. Hinman and the present applicant,Serial No. 317,674, filed October 30, 1952, now Patent No. 2,733,417,patented January 31, 1956, and assigned to the assignee of the presentapplication.

As disclosed and claimed in the copending application, the metal sleevebase to be assembled by the mechanism of the present invention is for anelectric lamp having a double-ended tubular glass envelope ofsubstantially closed configuration with its ends juxtaposed and directedtoward one another, such as the present commercial circular fluorescentdischarge lamps. The base comprises a sheet metal sleeve having the samedegree of curvature as the end portions of the lamp envelope and openends to receive the juxtaposed ends of the lamp envelope. It is composedof two longitudinally extending, interlocking sleeve sections offlexible metal having corresponding overlapping longitudinal edges atleast two of which are interlocking at their center portions only. Thecenter portion of the assembled sleeve base is held in an inwardlyflexed position by the interlocked edges of the sleeve sections, so thatthe base thus exerts a firm but yielding grip on the envelope endsembraced by the end portions of the sleeve to hold the base firmly andantiturningly on the envelope ends.

The principal object of the present invention is to provide an assemblymechanism of simple structure and operation for mounting and fasteningsuch a metal sleeve base on the juxtaposed ends of a tubular lampenvelope of substantially closed configuration.

Another object of the invention is to provide a mechanism capable ofholding an assembled base in a predetermined position on the ends ofsuch a lamp envelope, inwardly flexing the center portion of the basesleeve sections and permanently interlocking overlapping portions ofcorresponding edges of said sleeve sections while the said centerportions thereof are inwardly flexed to firmly attach the base on thelamp.

Still further objects and advantages of the invention will appear fromthe accompanying drawings, the appended claims and the followingdetailed description of a species thereof.

A feature of the assembly mechanism embodying the present invention is asupport for holding the lamp envelope and the base sleeve sections inproperly assembled relation, a locking toggle clamp for inwardly flexingthe center portion of the assembled sleeve and a multiple punch movableinto and out of the locked clamp at an angle suitable for punchingthrough and locking together the wall of overlapping portions of thecorresponding edges of the sleeve sections to secure the base on theends of the lamp envelope.

In the accompanying drawings,

Fig. 1 is a perspective view of the assembly mechanism as seen fromabove with a circular tubular lamp envelope mounted thereon and a basepositioned on the ends of 2,813,330 Patented Nov. 19, 1957 said envelopeand in the base holding member of said mechanism;

Fig. 2 is a top plan view of the base holding member of said mechanism;

Fig. 3 is a side elevational, partly sectional view of the base engagingmembers of the mechanism and a metal base mounted therein, and

Fig. 4 is an elevational view on an enlarged scale of a base attached tothe ends of a lamp envelope.

Referring to Figs. 1, 2 and 3 of the drawings, the assembly mechanism,herein illustrated in the form of a jig, comprises a flat support 1provided with lamp positioning and support members including two studs 3and 4 for supporting the circular tubular glass envelope 5 of afluorescent lamp and a block member 6 for engaging and supporting thelamp base 7.

The base 7 shown in Figs. 1, 3 and 4 is of the type disclosed andclaimed in the aforesaid copending application and described generallyabove. The base 7 comprises two longitudinal thin sheet metal sections 8and 9 each extending, at least in part, slightly more than degrees ofthe cross section of the base to make up a tubular sleeve which isslightly smaller in diameter at its center portion than at its open endswhich engage the juxtaposed ends of the lamp envelope. The axis of themetal sleeve has substantially the same degree of curvature as the axisof the juxtaposed end portions of the circular tubular envelope. Thecorresponding longitudinal edges of the sleeve sections 8 and 9 overlapand lie generally in plane including the circular longitudinal axis ofthe tubular.

hinged together at said edges to facilitate assembly of the sleeve onthe ends of the lamp envelope 1 and are locked together at said edgeswhen the base is fastened to the lamp envelope as described below.

The inner longitudinal edges of the sleeve sections 8 and 9 also overlapbut are adapted to be interlocked at their center portions only. Thus,as shown in Fig. 4, the sleeve section 9 has a center tab 13 which ispositioned behind the center portion of section 8 when the base isassembled on the lamp envelope and is interlocked there with by indents14 punched therethrough as described below in fastening the base on thelamp envelope by the assembly jig.

The assembly jig is constructed and arranged as described hereinafter toapply inward pressure on the center portion only of the assembled sleeveto flex this portion inwardly before the tab 13 is affixed to the sleevesection 8. The ends of the lamp envelope terminate in the end portionsof the assembled sleeve 8 and 9 as shown in broken lines in Fig. 4 sothat the center portion thereof may be flexed inwardly without crushingthe ends of the envelope. The end portions of the sleeve thus exert afirm but yielding grip on the ends of the lamp envelope embraced therebyto firmly hold the base on the envelope.

The base comprises also an insulating body 15 which is dimensioned toextend into the gap between the ends of the envelope 5 to limit relativelongitudinal'movement between the base and the envelope to less thanthat which would allow either end of the base to slip off either end ofthe envelope. Four spaced contact pins 16 are aflixed e19 mounted intheends of the sealed glass envelope 1 are connected to the contact pins.in assembling the base on the lamp envelope.

Atter"the'basei=has-been assembled 'on the ends of the lamp envelope asdescribed above, and the lamp is complete 'exceptiforthe'fasteningof-the'tab 13 of thesleeve secion 9 to the center portion of section- 8,the lamp is mounted on the'assernbly'jig with'the base 7 positioned inthe. block 6 and thelamp envelope l'resting on the studs 3 and 4 (Figs.1 and 3). The block 6'engages'the center portionionlyof the sleevesection 9 of the assembled base 7 and is provided with four spacedcavities 18 (Figs. 2 and 3) which receive the ends of the spaced contactpinslfi-offthei base. The studs 3-and 4, the block 6 and the" cavities18 in the'block are so spaced and dimension'ed'. with respect" to thelamp parts supported and engaged: thereby and with respect to each otherthat the assembled 'base 7 is sopositioned around' the ends of the lampenvelope that, after the base has been clamped totheenvelope by the jig,the curved longitudinal axis of therbase' 7 coincides with theprojection of the curved longitudinal axis of envelope 5 and theoverlapping longitudinaledges of the sleeve sections 8 and 9 liegenerally in-'a plane including the circular longitudinal axis of theenvelope.

The locking toggle clamp 19 of the assembly jig is provided with a jaw20 which is shaped and dimensioned to' engage the center portion only ofthe sleeve section 8 of theassembledbase 7. The jaw'20 also engages theblock 6" as shown in Fig. 3. The jaw 20 and the block 6 even in theclosed position of the clamp do not extend completely'aroundthecircumference'of the assembled base: 7 buton the contrary define a' gap(Fig. 3) giving access to the overlapping portions of the center tab 13of the sleevesection 9 and the center portion of sleeve section 8 sothatthese portions may be permanently fastened together by the multiplepunch 21 mounted on the-support 1-.

The-jaw- 20'of the toggle clamp 19 is mounted on an add the lever arm 22which has its opposite end pivoted at 23-onthe stand 24 permanentlyfastened to the support 1; The movements of lever 22 and therewith jaw20 are controlled by the forked lever arm 25provided with a handle 26-at its free end and having its forks -27 pivoted at 28 on the stand 24;The lever'arms 22 and-25 are connected by' links 29 pivoted'at 30'and 31to thelevers-22 and25, respectively.

The pivotpoints of the levers 22 and 25on the stand 1 andthe links 29 onthe levers 22 and 25' arearran'ged' in such manner as shown in'thedrawingthat asthe handle 26 is moved inward of the jigfrom the positionshown in Fig; 1 the jaw 20 is moved in the direction of the block 6. Asthe handle 26 is moved inward to bring'the' jaw 20 into engagement withthe block ;6' and the base 7 in the block, the;pivot points 30 and31-are moved relative'to each other and relative to pivot 28 of lever-25until the three pivots are aligned with each other and the free end oflever 22- is depressed'fully. Further inward movement of the handle 26'tends tolift the free end of' lever 22. I

Irr-the clamp 19illustrated' it isdesirable to move the handle 26 inwardbeyond the point at which the free end of arm 22 is fullydepressed,.because the jaw 20'is secured to the arm: by'the bolt 32(Fig; 3) slidablein the strap 33 welded to the arm 22 and isbiasedoutwardly of the armby the coiled metal spring 34 around the "boltand pressing against the arm 22 and the block 20. Thespring 34 iscompressed when the free end of'arm '22 is fully depressed .and remainsunder compression' even when the saidend of arm 22 is lifted slightlyfrom its fully depressed position. Thus, the force of the spring 34'tendingto lift the'said end' of arm 22 is made effective for locking thetoggle clamp 19 in holding position When the pivot points 28and 31-areon the side of pivot point'30 toward the free end of lever22-by=providing,-astopin the form of a fixed pin 15 extending throughlever 22 and into the path of movement of the links 29 to limit theinward movement of lever 25 under the force exerted by spring 34.

The spring 34 is not completely compressed even when the free end oflever 22 is completely depressed. The force exerted by the clarnp 19 "onthe assembled base 7 is determined solely by the stiffness of the spring34n The spring 34 is stiff enough to' flex the thin sheet metal of thecenter portions of sleeve sections 8 and 9 inward without impartingapermanent bend' thereto. The sur member-38'has a sleeve 39 integralwith one of its arms anda lever ;40 pivoted-at 41 on the other ofsaid-arms The lever 40 has a handle 42 at its free end. The punch21-also includes a shaft 43 extending through the sleeve' The shaft 43is connectedto the lever 40 by the links 44 pivoted at 39 and reciprocallongitudinally therein.

45 to the end of the shaft and at 46 to the lever 40 atapointbetween'the ends of the lever. A square chuck 47 is secured to theend of the shaft 43 and is heldthereon Three nail punches 49 are setinto cavities in the chuck 47 and are held therein by the set screw 48(Fig. 3).

by the set screws 50.

The nail punches 49- are dimensioned to move into and out of thegap-between the block 6 and the jaw 20 andto pierceand thus fastentogether the overlapped portions of the tab 13 and the" sleeve section8. The insulating. member 15 of the base 7 hasnotches 51 th'ereinyone ofwhich is shown in Fig. 3, behind the overlapping: areas of the tab 13and the sleeve section 8 to be pierced by:

thejrespective nail punches 49.

Force applied to the handle 42 of the lever 40to move it in a circulararc inward of the jig from the position shown in Fig. l is translatedinto a straight line motion by the links 44 "and the shaft 43 to movethe ends of: the nailpunches49 inward through the gap between the block6 andthe jaw 20 a suflicient distance to pierce throughthe overlappingportions of the tab 13 and the sleeve sec-' tion 8. The inward movementof the nail punches is limited by the bevelled edge 52 of the chuck 47which engages jaw 20 to'stop punches 49 after the piercing through ofthese base members. A shoulder 53 is provided on block 6 to hold jaw 20stationary against the force of the impact of chuck 47.-

As a result of the above-described combined operations" of the assemblyjig, the base 7 is permanently fastenedon the ends of the lamp envelope5 with the center portion thereof inwardly flexed and the end portionsthereof exerting a firm but yielding grip on the embraced ends of thelamp envelope.

The based lamp is removed from the jig by first moving" outward thehandle-42 of the punch 21 to pull the ends of the nail punches-49 out ofthe base 7 and then moving outward the handle 26 of the clamp 19 torelease the base 7. The based lamp then may be lifted from the assemblyjig andanother assembled base and lamp envelope mounted thereon forfasteningthe base'to the envelope ends asdescribed above.

What Iclaim as new anddesire to secure by'Letters Patent of the UnitedStates is:

1. An assembly mechanism for an electric lamp having a double-endedtubular 7 glass envelope of substantially closed configuration with itsends juxtaposed and directed toward one another and a tubular baseoverlapping'said envelope ends, enclosingthe gap therebetween-and com'prising a metal sleeve having longitudinally extending interlockingsections of thin flexible metal having corresponding over-lappinglongitudinal edges two of which are adapted to be interlocked at theircenter portions only, said mechanism comprising lamp support meansincluding a base sleeve engaging block, clamp means mounted in operativerelation to said block and having a movable jaw and including actuatingmeans for moving said jaw into and out of pressing engagement with saidblock, said clamp means comprising also a compression spring mountedbetween said jaw and said actuating means, said jaw and said block beingshaped and dimensioned to receive and press therebetween the centerportion only of said base sleeve and said spring being of sufficientstrength to flex said sleeve portion inwardly, the walls of said blockand said jaw in the closed position of said jaw defining an outwardlyopening gap opposite the center portions of the edges of the sleevesections adapted to be interlocked at said portions only, said mechanismcomprising also piercing punch means positioned and dimensioned to passthrough said gap into piercing engagement with said overlapping edgeportions of the base sleeve to interlock said portions.

2. An assembly mechanism for an electric lamp having a double-endedtubular glass envelope of substantially closed configuration with itsends juxtaposed and directed toward one another and a tubular baseoverlapping said envelope ends, enclosing the gap therebetween andcomprising a metal sleeve having longitudinally extending interlockingsections of thin flexible metal having corresponding overlappinglongitudinal edges two of which are adapted to be interlocked at theircenter portions only, said mechanism comprising lamp support meansincluding a base sleeve engaging block, clamp means mounted in operativerelation to said block and having a movable jaw and including actuatingmeans for moving said jaw into and out of pressing engagement with saidblock, said clamp means comprising also a compression spring mountedbetween said jaw and said actuating means, said jaw and said block beingshaped and dimensioned to receive and press therebetween the centerportion only of said base sleeve and said spring being of suflicientstrength to flex said sleeve portion inwardly, the walls of said blockand said jaw in the closed position of said jaw defining an outwardlyopening gap opposite the center portions of the edges of the sleevesections adapted to be interlocked at said portions only, said mechanismcomprising also piercing punch means positioned and dimensioned to passthrough said gap into piercing engagement with said over lapping edgeportions of the base sleeve to interlock said portion, said punch meansincluding a chuck engageable with said jaw to limit the inward movementof said punch on piercing of the said base edge portions.

References Cited in the file of this patent UNITED STATES PATENTS1,231,889 Herr July 3, 1917 1,706,880 Gustin Mar. 26, 1929 1,729,267Hathaway Sept. 24, 1929 2,011,926 Birmingham Aug. 20, 1935

